Process of making a neutral sodium salt of lactalbumin.



35 tinucd.

40 bccu PATENT OFFICE.

UNITED STATES ERNST FISCHER, OF GRONAU, NEAR ELZE, AND PETER BERGELL, OFBERLIN,

GERMANY.

PROCESS OF MAKING A NEUTRAL SODIUM SALT OF LACTALBUMIN.

Specification of Letters Patent.

Patented Nov. 30, 1909.

N Drawing. Original application filed April 25, 1908 Serial No. 429,129.Divided and. this application filed This invention has reference toimprovelnents in a process of producing a pure and neutral'sodium saltof lactalbuinin.

This application is a division of our application for Letters Patent ofthe United States for process of producing a pure and neutral sodiumsalt of lactalbumin filed April 2.). 1905. bearing Serial No. 429,129.

A rcccnt discovery that lactalbuinin is contained in milk in form of aneutral s0luble alkali compound, that is in form of an alkali suit, ll2lresulted in the invention of new proccsscs of producing such a compoundand thc prcscnt invention has for its object such a proccss fullydescribed hereinaft r.

it known that lactalbulnin may be obtaincd from skim-milk on a largescale by adding an acid. rcmoving thc casein thereby prccipitatcd andhcatiug thc solution now lrcc l'rom cascin whcrcby thc lactalbumin isprccipilatcd. 'lhc Lactalbumin thus obtaincd forms a coagulatcd masswhich is in- .soluble in walcr and must be dried and freed from fatbol'orc thc trcatmcnt can "be con- .l ol' dissolving such laclalbumin,\vhcn in a d. condition. an excess of alkali is necessary. ln gcucral.it) gr. ol' hydroxid ol' sodium txaUlll will sullicc l'or dissolving 1kg. of dricd lactalbumin which has p irccd l'rom l at. The solution isnot ncutral. but strongly alkalinc. and special precautions must bc.takcu l'or rcnioving the cxccss ol alkali. 'lhc applicants thendiscorcrcd that: thc lactalbumin \vhcn precipitatcd from tho alkaliucsolution by carecquivalcnt quantity of same. l kg.ol' l'rcshlyprccipitatcd liu-talbumin thcu rc uircs but. 26 gr. ol sodium hydroxidl'or cll'cctiug tho transl'ormation into a purc and neutral alkali salt.'lhi.- is easily and quickly el Serial No. 459,039.

1 fected by means of an alcoholic solution of fixed alkali preferably ofsodium hydroxid. If however the dry and fat free ordinary commerciallactalbumin is directly treated with alcoholic sodium hydroxid then somesalt is formed but the resulting product is neither neutral nor uniformin composition nor is it completely soluble.

In carrying the present invention into effect we proceed substantiallyas follows: The ordinary commercial lactalbumin is first dissolved in anexcess of alkali. 1 kg. requires about 30 gr. of sodium hydroxid. Fromthe resulting strongly alkaline solution the lactalbumin is thenprecipitated by carefully adding an acid. preferably hydrochloric acid.The freshly precipitated lactalbumin is washed with water and pressedand suspcndcd in alcohol to which is gradually added a conccntratcd.aqueous solution of sodium hydroxid containing 26 gr. of

of sodium hydroxid to (37')?! of water. The suspended freshlyprecipitated lactalbumin combines with the sodium hydroxid but thc newproduct docs not dissolvcv in the alcohol solution, it. remains thcrcinin such l'orm that thc solution may bc easily romovcd by liltratiou.'lhc rcmaiuiug liltratc is ucutral and the salt. al'lcr having bccndricd rcprcsouls a ucutiral purc sodium compound of lactalbumin.

The above (ltHClllMtl observations and reactions cstablisli beyond doubtthat a ncutral alkali salt of laclalbumiu cxists. 'lhc imp rtance ofrecovering this substance in order tousc it for feeding human beings isapparcnt from thc fact that. in thc mothcrs milk lactalluuuiu iscontained in a much larger quantity than in cow's milk.

In order to make the invention clear the following oxample. is hcrcwithgiven. It) kg. of ordinary comn'icrcial lactalbui'niu arc suspcndcd inwatc' and dissolved by adding a solution of sodium hydroxid containing(100 gr. ol' samc. 'lhc solution thus obtained "is ucutralizcd byhydrochloricacid and lhcn trio gr. of hydrochloric acid arc addcd inaddition to thc quantity required for neutralizing w'hcrcbv thc.htctalbluniu is precipitatcd l'rom thc clcar solution in form ofscparatcd by liltratiou and the precipitate is thoroughly wash'cd \Vllllwater. Now tho i l l l i l l dium hydro'xid in the proportion of 33%.

llakc-. 'lhc. prccipitatc and solution are llu'u liquid, was ing thefree water is removed by means of a filtering press and the dry cakethus obtained reduced and suspended 1n alcohol of 90%. To this 1sgradually added, While constantlystirring, a concentrated aqueoussolution of sodium hydroxid containing 260 gr. of the latter in theproportion of 33% of sodium hydroxid to (i(% of water. After from 14; to2 hours the alcohol becomes neutral and is filtered oil, the compoundpressed again and the alcohol still adhering to the cornpound removed byether. Finally the product is dried at a low temperature to evaporatethe ether. The product thus obtained is reduced to a fine owder. Whendissolving same it is essentlal to note that a large quantity of waterat once added to the powder will not give a complete solution and Whenagitated With the water the mass will again settle at the bottom. If,however, the powder is stirred at first with a very little water untilit swells and gradually more Water is added While stirrin a durablesolution is obtained. One gr. oi the sodium lactalbumin salt requires 50grl of water. However other concentrations may be produced and in higherconcentrations the solution certainly does not flow so easily. Suchsolutions are distinguished from solutions of the casein salts by takingup completely the sodium lactalbumin Without leaving an insolubleresidue as is the case when casein salts are dissolved.

We claim as our invention:

1. The process of producing a neutral alkali salt of lactalbumin,consisting in dissolving dried, fat free lactalbumin in an excess o anaqueous solution of fixed alkali, precipltating the lactalbumin by meansof an acld, se )aratlng the recipitatefrom the lily precipitatedlactalbumin with Water, removing the water, reducing and suspendin theprecipitate in alcohol, adding gradua ly a c ncentrated, aqueoussolution of fixed alkali ontaining a chemically equivalent quantity 1?same, al-

lowing the lactalbumin and al ali to comblne and removing the neutralalcohol solution.

2. The process of producing a neutral alkali salt of lactalbumin,consisting in dissolving dried, fat free lactalbumin in an excess of asolution of fixed alkali, neutralizing the solution, precipitating thelactalbumin by means of an ac1d', separating the precipitate from theliquid, washing the freshly precipitated lactalbumin with water, freeingit from the Water, suspending it in alcohol, adding a concentratedaqueous solution of fixed alkali containing a chemically equivalentquantity for binding the lactalbumin, removing the alcohol solution whenit is neutral by pressure, removing the traces adhering to the compoundby ether and allowing the ether to evaporate.

3. The process of producing a neutral sodium salt of lactalbumin,consisting in dissolving dried, fat free lactalbumin in an ex-' cess ofa solution of sodium hydroxid, precipitating the lactalbumin withhydrochloric acid, separating the precipitate, Washing it with water,freeing it from the water, suspending it in alcohol, adding aconcentrated aqueous solution of sodium hydroxid containing a chemicallyequivalent quantity for binding the lactalbumln and removing the alcoholwhen neutral. 7 q

4. The process. of producing a neutral sodium salt of lactalbumin,consistingain dissolving and reprecipitating the lactalbumin, separatingthe freshly precipitated lactalbumin from the liquid and Washing it withWater, freeing it from Water, suspending it in alcohol, adding aconcentrated aqueous solution of soduiin hydroxid containing achemically equivalent quantity for binding the lactalbumin, and removingthe alcohol when neutral.

5. The process of producing a neutral sodium salt of lactalbumin,consisting in washing the freshly precipitated lactalbumin with water,freeing it from the water, suspending it in alcohol, adding aconcentrated aqueous solution of sodium hydroxid containing a chemicallyequivalent quantity for binding thelactalbumin and removing the alcoholwhen neutral.

Signed at Berlin, Germany, this 7th day of October, 1908.

ERNST FISCHER. PETER BERGELL. Witnesses:

HENRY HAsPnR, WOLDEMAR HAUPT.

